How much do night lenses cost to restore vision and how to use them? Night lenses for vision correction Night lenses for eyes

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What are night lenses?

Night or orthokeratology lenses is one of the most modern and effective methods of non-surgical vision correction. The essence of the method is to influence the cornea ( part of the eye) to improve visual acuity. The undoubted advantage over other methods is that the patient does not need to constantly wear glasses or contact lenses. The effect of using night lenses is similar to laser vision correction, but for a relatively short period of time.

Currently, night lenses are very common in developed and developing countries. The field of ophthalmology that develops, manufactures and selects them is called orthokeratology, and doctors, respectively, are called orthokeratologists.

In clinics or the media, you may encounter the following synonyms for the term "night lenses":

orthokeratological lenses;
ortholenses;
OK lenses;
"night" vision correction;
night wear lenses, etc.

According to statistics, today millions of people around the world use night lenses. New developments in this area allow the use of this technology to help patients with various problems ( myopia, farsightedness, astigmatism, etc.).

What is the difference between rigid solid) night lenses from regular contact lenses ( daytime)?

Vision correction with night and ordinary day lenses has a number of significant differences. First of all, the very principle of operation of these methods differs. To make it easier for the patient to choose the appropriate method of vision correction, he needs to be well aware of the differences between them.

Differences from conventional daytime) contact lenses from night

Daily contact lenses	Overnight Orthokeratology Lenses
The lens transmits light and refracts it, correcting the refractive error ( refraction). In other words, the lens is an additional refractive medium, in addition to the lens and cornea.	The night lens is not designed to be corrected by refraction of light. During the night, it only changes the shape of the cornea, and a person sees well during the day without additional devices ( refraction only through the own cornea and the lens of the eye).
Lenses are worn during the day, as they provide good vision when worn. When the patient removes the lenses, vision deteriorates.	The lens is worn at night and does not look through it ( eye closed). Vision improves for 8-10 hours after its removal in the morning.
Currently, for the correction of nearsightedness and farsightedness, soft contact lenses are mainly used, since a person feels more comfortable in them.	Night lenses are only rigid, as they must shape the outer surface of the cornea, leaving a kind of "cast" on it.
The selection, manufacture and purchase of ordinary contact lenses is much easier and cheaper than in the case of night lenses.	Lenses are selected by certified specialists and are made individually for a particular patient.
The lifespan of regular contact lenses can vary. Usually it is less than in the case of night lenses. There are even disposable contact lenses that are not meant to be reused.	The life of night lenses is much longer. The same rigid lens is used multiple times to secure the new shape of the cornea and ensure good vision after the lens is removed.
Daily lenses allow you to correct vision even with large refractive errors ( refraction) -6 diopters or more, as well as with astigmatism.	Night lenses are not used in case of large refractive errors ( myopia greater than -6 diopters). There are also limitations with astigmatism. That is, night lenses can be used in such cases, but they will not be able to give one hundred percent vision, but will only improve it ( for example, they will raise visual acuity from 70 to 90 percent).

Thus, night lenses have fundamental differences from conventional contact vision correction and are considered an independent method of correction.

How night lenses work

To better understand how a night lens works, it is necessary to understand how the human eye acquires an image. This requires light that will be reflected from surrounding objects and enter the eye. Various lighting characteristics ( wavelength, intensity, etc.) are perceived by the eye and deciphered by the brain, which is interpreted as an image of the surrounding world. All anatomical structures of the eye ensure the refraction and focusing of light rays on light-sensitive cells.

The light-sensitive and refractive system of the eye consists of the following main parts:

cornea- the most powerful refractive lens, which is responsible for focusing the rays inside the eye;
pupil- a hole in the iris that regulates the amount of incoming light;
lens- a spherical lens that can change the curvature, due to which a person sees well at different distances ( adjustable degree of refraction of rays);
retina- the inner shell of the eye, in which there are cells that transform light rays into bioelectric impulses and direct them to the brain.

The most common vision problems ( nearsightedness, farsightedness, astigmatism, etc.) appear due to the fact that the cornea or lens does not provide the necessary refraction of light rays. As a result, the focal point is obtained behind the retina or in front of it, and the image quality drops - visual acuity decreases.

The action of the night orthokeratological lens is aimed at changing the shape of the outer surface of the cornea. Since this is the most important layer for refraction of light rays, even a small change in curvature affects the clarity of the image ( similar to how sharpening is done in optical instruments). If a person with myopia or hyperopia needs to change the curvature of the cornea, vision will be one hundred percent.

The night lens provides vision correction in the following ways:

the inner surface of the lens exactly repeats the shape of the outer surface of the cornea, but with slight changes ( as if pressing the outer layer and changing the radius of curvature);
these changes are accurately calculated by the doctor when choosing a lens and are aimed at the desired change in curvature;
during sleep, the dressed lens forms, as it were, a cast of the outer surface of the cornea, which persists for some time;
after removing the lens, the cornea "remembers" a new shape, which provides the best visual acuity;
during the day this form is lost ( property of living cells and tissues to restore their original shape), but the next night the lens is put on again, and the shape is corrected again.

Thus, the night lens gives an effect similar to the effect of laser vision correction surgery. However, during the operation, the desired shape of the cornea is given using a special laser. The effect of such an intervention will no longer be temporary, as from the action of a night lens.

Pros and cons of using night lenses for vision correction

Like any correction method, night lenses have their advantages and disadvantages. Patients, who are going to switch to night lenses, can get acquainted with them in detail at a consultation with a specialist. The fact is that some people may have medical contraindications that a person does not know about, but which will not allow you to choose night lenses.

Advantages and disadvantages of night lenses

Advantages	Flaws
100% ( or close to this) visual acuity without wearing lenses during the day	Night lenses are more difficult to fit and manufacture, and specialists who can make such a fit are harder to find.
Opportunity to engage in active sports	Individual selection and production explain the higher cost ( compared to other correction methods)
The ability to correct people with specific professions ( pilots, scuba divers, etc.)	A number of patients have problems getting used to the lenses - at first they cannot fall asleep in them due to unusual sensations
Lenses are rarely changed once every six months, but more often once a year)
No discomfort that some people experience when wearing daily lenses
Therapeutic effect - inhibition of progressive myopia in children of primary school age
The ability to use lenses in a wide age range ( starting from 6 years old)
Low complication rate ( compared to conventional daily lenses)

Can night lenses completely get rid of glasses and correct vision?

Nowadays, for many people, night lenses have really become a full-fledged replacement for glasses or regular contact lenses. From the point of view of optics, there is no fundamental difference in how exactly the refraction correction occurs ( refraction of rays). It is important that the light rays accurately hit the retina, which will ensure one hundred percent visual acuity.

At the moment, there are four main types of vision correction:

glasses- the corrective lens is located in front of the eye;
daily contact lenses- the corrective lens is located on the surface of the cornea;
night lenses- a lens worn at night temporarily corrects the shape of the cornea, due to which it correctly refracts light rays even after the lens is removed;
laser vision correction- with the help of a laser, the surface of the cornea is changed in the right way, but the effect is no longer temporary ( as with night lenses).

The choice of correction method depends on the patient's lifestyle, existing vision problems, indications and contraindications. Thus, night lenses in most cases can completely replace glasses, daytime contact lenses or laser correction, although each method has its own advantages and disadvantages.

Indications and contraindications for the use of night lenses

Like any other method of vision correction, night lenses have their indications and contraindications. From a medical point of view, they have an undeniable advantage over spectacle correction, daily lenses and laser correction. The use of night lenses, when properly fitted and used, can restore 100% vision to most patients. In this case, a person will see during the day without additional devices, and the “image” in his eyes will not have distortions along the periphery, as happens, for example, when wearing strong glasses. In addition to this benefit, there are a number of medical indications for orthokeratology correction. These are cases where a night lens is the best choice.
There are the following indications for the use of night lenses:

myopia ( myopia) with an indicator up to -8 diopters ( without astigmatism);
progressive myopia in children older than 6 years and adults ( it has been proven that it is night lenses that most effectively inhibit the process of gradual deterioration of vision);
astigmatism up to 5 diopters ( the limit of the indicator depends on the manufacturer and model of the lens);
farsightedness ( hypermetropia) with up to +4 diopters ( the limit of the indicator depends on the manufacturer);
patients who, for one reason or another, cannot undergo laser vision correction;
patients who, due to their occupation, cannot wear glasses or day lenses ( work in dusty conditions, athletes, etc.);
keratometry index ( associated with individual characteristics, shape and structure of the cornea) ranging from 37.5 to 50 diopters.

In the event that a patient is not completely fit for the indications, but wants to use night lenses, he must accept the risk that a complete correction ( 100% vision) cannot be achieved. For example, a patient has myopia with an indicator of -9 diopters. With this vision, a person sees very poorly ( can't even read the top line on a standard vision chart). Even the best night lenses will not restore his 100% vision, but they will significantly improve it ( compensate from -9 to -1 or -2, which will allow him to live a completely normal life). For a complete correction, other methods will be preferable. Understanding in detail whether there are indications for the use of night lenses in a particular patient will help ophthalmologist ( enroll) , optometrist or orthokeratologist.

There are quite a few contraindications to the use of night lenses, but they are relatively rare. All contraindications are divided into absolute and relative. Absolutes prohibit lens fitting because the potential risk of this correction method outweighs the expected benefit. For example, with weak immunity ( against the background of AIDS or treatment with certain drugs) the constant wearing and removing of lenses can potentially lead to infection . In the normal patient, this risk is minimal, as immunity will stop complications from developing, but in immunocompromised individuals, the development of infection can lead to permanent blindness. Relative contraindications suggest that lens fitting is possible under certain conditions. For example, during pregnancy and sometimes during breastfeeding) do not pick up night lenses. However, the potential problems are not as serious and the contraindication is temporary ( after childbirth, nothing prevents a successful correction).

Contraindications to the use of night lenses

Absolute	relative
Inflammatory processes in the eye ( conjunctivitis, keratitis, etc.)	Pregnancy and lactation
Past history of keratitis inflammation of the cornea)	wide pupil ( wider than 4 mm under medium-intensity lighting and at rest)
	Clouding of the cornea
Some types of corneal deformities ( keratoconus, keratoglobus, etc.)	The period of treatment with certain drugs ( corticosteroid group, chemotherapy, some hormonal drugs, etc.)
Certain systemic infections and inflammatory diseases ( until recovery, night lenses are not selected)	Eye manifestations of allergic reactions ( inflammation, tearing, etc.)
Patients with one eye	Past laser vision correction
Benign and malignant neoplasms of the eye	Some autoimmune diseases
Some mental illnesses	Some diseases of the endocrine system ( hormonal)
Diseases of the nervous system, accompanied by nystagmus ( uncontrolled pupil movement)	Oncological diseases
Severe immunodeficiency ( weakening of the immune system against the background of various diseases)	Moderate dry eye syndrome

Clarifications regarding the indications and contraindications for the use of night lenses can be given by an orthokeratologist after examining the patient. In some cases, the patient may agree to an incomplete correction. This means that night lenses will improve vision, but due to existing contraindications, they will not allow you to achieve one hundred percent visual acuity.

It is dangerous to ignore contraindications or hide diseases from a doctor who selects lenses. The patient at the same time risks that the developed complications in the future will seriously impair vision or general health.

Night lenses for various vision problems ( myopia, hyperopia, keratoconus, presbyopia, astigmatism, strabismus, etc.)

Initially, night lenses were used only to correct myopia, and within very modest limits. At present, the accumulated experience of their use and technical progress make it possible to use this method to help patients with a wide variety of problems. Each individual case has its own subtleties, and the possibilities of this method are still not universal.

Orthokeratology overnight lenses can be used for the following vision problems:

Myopia ( myopia). For people with nearsightedness, night lenses are often the ideal correction method. They can restore 100% vision to patients with myopia ranging from -0.25 to -6 diopters. In addition, it is in the case of myopia that night lenses have a therapeutic effect, and not just the ability to correct the error of light refraction. Unlike glasses or ordinary lenses, they slow down or even completely stop the gradual deterioration of vision. For most patients, this is a very urgent problem, since many types of myopia are prone to progression. Night lenses are especially suitable for children and adolescents with progressive myopia.
Farsightedness ( hypermetropia). For a long time, night lenses could not correct farsightedness. The difference from the correction of myopia lies in the very nature of the refraction of rays. A lens worn over the cornea can naturally reduce its curvature ( that is, it almost does not press on the edges, but presses on the central part). This is how myopia is corrected. With farsightedness, on the contrary, it is necessary to make the cornea more convex, weakening the pressure in the center and increasing it at the edges. Unfortunately, this disrupts the circulation of the tear fluid and impairs the nutrition of the cornea. In this regard, night lenses for farsightedness, which have recently appeared on the market, have a rather complex structure. They are much harder to find fewer clinics and manufacturers), and the possibilities of correction are lower ( currently up to +4 diopters under other ideal conditions). Also, this type of night lenses often gives various complications and side effects.
Presbyopia ( age-related visual impairment). Presbyopia, or age-related farsightedness, usually appears in people over 40 years of age. It is quite difficult to correct it with the help of night lenses and it is possible only in the early stages. Not all clinics involved in the selection of night lenses can correct presbyopia by this method.
Astigmatism. Astigmatism is an irregular shape of the cornea, in which the radius of its curvature is different in different axes. As a result, the patient gets, as it were, different visual acuity in the same eye ( for example, - 2 on the vertical axis and - 1 on the horizontal). Small values of astigmatism in myopia can be corrected with the help of night lenses. True, in this case, the selection of the correct lens is more difficult.
Strabismus. Strabismus can be caused by various reasons, and only for some of them night lenses will be a successful method of correction. The problem is that statistically the largest number of cases of strabismus develops in patients with farsightedness ( convergent strabismus). Night lenses do not correct this problem well. In the case of divergent strabismus ( due to myopia) the use of night lenses is very effective and can even completely eliminate the problem for some time, that is, correct strabismus without surgery. For patients with strabismus due to eye trauma or neurological disease ( like after a stroke) night lenses are a neutral option. They can correct myopia ( if she is) in each eye separately, but the strabismus will not disappear and many vision problems will remain.
Keratoconus and keratoglobus. Keratoconus and keratoglobus are variants of pathological changes in the shape of the cornea. In both cases, its center is strongly raised relative to the peripheral part, which causes a strong deterioration in vision. Unfortunately, in such cases, night lenses cannot correct the defect. Both keratoconus and keratoglobus are contraindications for this correction method.

All of the above vision problems, in fact, are more correctly called not diseases, but anomalies or refractive errors ( refraction of light). The problem in these cases is optical in nature and can be corrected by applying a suitable correction method. Diseases of the eyes dry eye syndrome, conjunctivitis, cataract, etc.) are of a different nature. They are caused by changes in the structure of the eye, infection or inflammation. In such cases, night lenses will not only not help the patient, but may even aggravate the course of the disease. The underlying disease must be treated first, after which it will be possible to consider the possibility of their use.

Use of night lenses in children, adults and the elderly

In terms of age, night lenses are an almost universal method of vision correction. They are suitable for all patients over 6 years of age. This limitation is explained not only by the changes that occur in the process of growth, but also by problems with learning. The effectiveness of the correction with night lenses depends not only on the selection, but also on the correct use of the lenses by the patient. Even if parents put on and take off lenses for a child, he may not be attentive enough ( out of ignorance). Because of this, the risk of complications is high.

In general, the use of night lenses at different ages is as follows:

Children over 6 years old. For school-age children with progressive myopia ( vision deteriorates from year to year) night lenses are the best means of correction. In this case, this provides not only one hundred percent vision during the day, but is also a therapeutic measure, as it slows down or even completely stops the growth of myopia. This problem is very relevant especially for primary school age. According to statistics, in developed countries every third child needs myopia correction. After the selection of night lenses, parents should first control the process of putting them on or taking them off ( or do it yourself) to teach the child to use this correction method correctly.
Teenagers. Adolescents are able to put on and take off lenses themselves, as well as care for them. However, by law, the selection of lenses still takes place with the participation of parents, and they receive appropriate instructions.
Adults up to 40 - 45 years. In the case of adult able-bodied people, correction with night lenses is perhaps the best choice. The exception is the presence of contraindications or refractive errors that cannot be corrected by this method ( high degree of nearsightedness, farsightedness or astigmatism).
Adults over 40 and the elderly. Most people over 40 years of age some later) develops presbyopia or age-related farsightedness. This problem tends to worsen with age, as it is caused by age-related changes in the structure of the eye. Modern night lenses are able to correct vision for presbyopia. The problem is that as vision deteriorates, the lenses will have to be replaced more often with stronger ones. The expediency of using this method of correction in each case must be discussed with the attending ophthalmologist.

Can night lenses be difficult to fall asleep?

The vast majority of patients do not experience serious difficulties in getting used to night lenses. In the early days there may be some discomfort ( especially in case of correction of severe myopia), but this is only temporary. Gradually, the patient gets used to falling asleep in night lenses and does not experience any discomfort. A little longer this period of addiction can last in children. But, as practice shows, they, having felt the effect of this correction method, quickly adapt and sleep well in night lenses.

Are there any complications or side effects when wearing night lenses?

Orthokeratological vision correction with night lenses is recognized as a safe method, which is confirmed by numerous studies in recent years. It does not give any permanent side effects, and the complication rate does not exceed 0.5% with the correct use of lenses. In practice, most of these complications are associated with infection in the eye due to improper storage or care of lenses, or during the process of putting on and taking off lenses.

Patients with the use of night lenses may experience the following complications:

Redness of the eye. Redness of the eye is one of the most common symptoms in ophthalmology and can be caused by a variety of reasons. If the eye began to redden just after the start of using night lenses, you should stop using the lenses and contact the clinic where the lenses were selected. The doctor will determine the cause of this symptom and prescribe the necessary treatment. As a rule, the patient will not have to completely abandon the night correction. It will only be necessary to take a short break for the duration of treatment ( if needed).
Viral conjunctivitis. Viral conjunctivitis is one of the most common eye infections. A virus that causes inflammation can enter the eye both from dirty hands when putting on or removing lenses, and from the air if there is a sick person nearby. This complication is not directly related to the use of night lenses. With redness of the eye, tearing and other signs of inflammation, you should consult a doctor and undergo a course of treatment. After recovery, the patient can continue to use night lenses.
Allergic reactions. Allergy, as a rule, does not occur on the lenses themselves, but on the components of the solution that is used to care for them. First signs ( redness, swelling of the eyelids, etc.) appear in the first hours or days after the start of the use of night lenses. Patients need to see a doctor to prescribe antihistamines ( corticosteroid drugs in this case are usually not required). After that, the patient needs to go to the clinic where the lenses were selected and ask to prescribe a different solution to care for them. During the period of pronounced manifestations of allergies, night lenses are not used.
Adhesion of the lens to the cornea. Lens sticking to the cornea is a relatively common problem, but does not always require a visit to a doctor. When the patient is explained how to use night lenses, they are shown some standard removal techniques and explained that in case of sticking, special eye drops can be helped. If even after drops the lens is poorly removed, you should definitely consult a doctor. The problem may be in insufficient secretion of tear fluid ( dry eye syndrome) or changes in its composition. In these cases, the patient may require additional treatment and further consideration will be given to the use of night lenses.
microbial keratitis. Microbial keratitis is the most dangerous of the complications that can occur when using contact lenses. It appears when pathogenic bacteria are introduced to the surface of the cornea. As a result of the vital activity of microbes and the accompanying inflammatory process, the destruction of the surface layers of the cornea begins with the formation of an ulcer. Wearing lenses in this case is immediately stopped. The patient urgently needs to go to the ophthalmological clinic. Quite often, microbial keratitis and corneal ulcer require inpatient treatment ( the patient is admitted to the hospital). Delay in treatment even for a few days can lead to irreversible deterioration of vision and even blindness. Further use of night lenses is not excluded, but it is continued only with the permission of the doctor after complete recovery.

Thus, the complications that can occur when using night contact lenses are not so many. If any unusual symptoms appear, the patient should consult an ophthalmologist ( preferably to the clinic where the lenses were selected) and temporarily stop using this correction method.

What should I do if my eye hurts in the morning after removing the night lens?

A properly selected night lens does not cause any pain during use. If a person removes the lens in the morning and experiences pain, this may indicate any complications or comorbidities. In any case, the appearance of such a symptom cannot be ignored. You should contact the doctor who selected the lens, and find out the cause of the pain.

The causes of discomfort after removing the lens in the morning may be the following diseases or disorders:

displacement during sleep due to unconscious hand movements);
development of conjunctivitis or other infectious complications ( often due to misuse of the lens);
inflammatory processes in the area of the eyelids or surrounding tissues ( as a rule, such diseases are not directly related to the use of lenses).

In general, pain in the eye in the morning after removing the lens is a very rare occurrence. The lens is designed in such a way that it cannot damage the eye without external intervention ( if you do not press on it and do not receive blows in this area).

What are the consequences of giving up night lenses?

In principle, there are no negative consequences after the refusal of night lenses in patients. If the patient used this method of correction for a relatively short period of time ( several weeks or a month), then the cornea is not even fully accustomed to the new shape. Within 1 to 2 weeks after the withdrawal of night lenses, visual acuity will return to baseline, as before using them. If the patient has regularly used night lenses for years, then vision will deteriorate more slowly, since a “cast” remains on the cornea, which still corrects vision. Within 1 to 2 months, vision will gradually deteriorate until it returns to baseline anyway.

Rules for the use of night lenses

The mechanism of correction with night lenses is built in such a way that to achieve a good effect, you need not only to choose and make the lenses themselves correctly, but also to use them correctly. The speed of addiction, the quality of vision and the risk of complications largely depend on the efforts of the patient himself. That is why the selection of lenses includes several visits to a specialist, during which the patient receives detailed instructions.

How to put on and take off night lenses on your own and help your child put lenses on?

Suction cups for removing night lenses

Many patients who have no prior contact lens experience experience some difficulty in putting on and taking off night lenses. Prior to acquiring the necessary skills, they are often recommended special suction cups. These are small devices for removing the night lens in the morning. The suction cup is applied to the center of the dressed lens and slightly pressed. After that, with a gentle movement from the eye and sideways, the lens is removed from the cornea. Some patients ( especially children) are initially frightened when a foreign object is brought to the eye. In practice, they gradually get used to it.

Using suction cups to remove night lenses has the following advantages:

many patients find this method faster and more comfortable;
from a medical point of view, the use of a suction cup is safer, since the chance of infection when removed with fingers is higher;
the chance to injure the cornea is less;
the suction cup makes it easier to help another person remove the lens ( for example, they are useful to parents whose children wear night lenses).

Attention should be paid to the method of storage and care of suction cups. For their storage use a special container. Suction cups, like night lenses themselves, must be regularly treated with a special solution that will prevent infection from entering the eye during removal. To "unstick" the lens from the cornea, when it is poorly removed, you need to drop a special solution.

If a patient has difficulty putting on or taking off night lenses and decides to purchase suction cups, they should contact the doctor who fitted the lenses. The orthokeratologist will explain to the patient in detail how to use this device and show how to remove the lenses correctly. After acquiring the necessary skills, these manipulations will not present any difficulties.

Before removing the lens in the morning, it is important to make sure that it has not slipped off the cornea. If you try to stick a suction cup to a cornea that does not have a lens on it, you can injure your eye and require treatment. However, most patients feel the lens well and the chance of making such a mistake is minimal.

How much sleep do you need at night to have a good effect from night lenses?

The principle of operation of night lenses is that, being in contact with the anterior surface of the cornea, they change its shape, due to which vision is corrected. For a good effect, they must be used regularly, and the contact time must be sufficiently long. Studies show that the minimum duration of wearing should be 6 - 7 hours per day. Since the lenses are supposed to be used during sleep ( The recommended amount of healthy sleep is 6-8 hours.), then you need to try to sleep just that much. The maximum duration is theoretically unlimited, but according to the recommendations, you should not regularly exceed the period of 10 hours.

It should be noted that you can sleep in night lenses not only at night. Daytime sleep also contributes to the consolidation of the therapeutic effect.

Sleep lasting 4-6 hours does not provide good vision correction for the following reasons. The outer layer of the cornea, which the lens gives the necessary shape, loses it over time. This is partly due to the elasticity of living tissues, and partly due to the gradual death and division of cells. After removing night lenses, the process of returning to its original shape begins almost immediately. That is why a 100% correction is achieved in a short time ( for the day), and then you need to keep fit again and wear orthokeratology lenses again at night. A short sleep will simply give a non-100% correction ( visual acuity will be 90 - 95 percent). In addition, it will be good in the first half of the day, and in the late afternoon, vision will begin to deteriorate slightly. Even if a person does not feel this minimal difference, his body will let you know. Such changes in visual acuity during the day can lead to fatigue, headaches, dizziness. The exception is patients with slight myopia ( up to -2 diopters). The minimum correction is achieved in a shorter time, and the effect of it is longer. Some patients with a small minus may even wear lenses not every night, but every other time.

Can I wear night lenses during the day?

In principle, there is no prohibition on wearing a night lens during the day. The patient in this case will have the same visual acuity ( ideally 100%) as in normal use of this method. The night lens is transparent and, being on the surface of the cornea, does not interfere with vision, and its internal relief performs correction even with the eye open. However, most experts do not recommend using night lenses in this way.

Wearing a night lens during the daytime has the following significant disadvantages:

an orthokeratological lens is not as comfortable for the eye as a regular soft lens, and a person may simply be uncomfortable;
the meaning of this correction method is lost - to achieve good visual acuity in the daytime without any additional devices;
the night lens is rigid in structure, it keeps worse on the surface of the cornea and may fall out during the day;
visual acuity will be the same both with and without a lens ( if she was dressed for the night);
Constant wearing of the lens during the day and at night impairs the nutrition of the eye ( tear fluid circulation and corneal respiration), which can lead to various complications.

Do I need any eye drops when wearing night lenses?

Each patient using night lenses needs to have special drops that act as artificial tears. As a rule, these drops are selected and prescribed by a doctor. The meaning of the drops is to facilitate the process of putting on and taking off night lenses. They are especially important for patients with mild dry eye syndrome. Wearing a night lens on a "dry" eye, in which there is not enough tear fluid, increases the risk of corneal damage and infection. Detailed instructions for the use of drops are given to the patient by the doctor in the process of selection and training. The mode of use of drops, their type and quantity may differ in different patients, since each person may have their own problems, indications and contraindications.

Is it possible to pick up night lenses after wearing ordinary lenses or glasses and vice versa?

Almost all methods of vision correction are interchangeable, and the patient can switch from one method to another at will. At the same time, there are some features and recommendations that should be followed. Basically, this concerns the transition from night lenses to other methods of vision correction.

After night lenses, the patient can switch to the following correction methods:

Glasses. There are no obstacles to the transition to glasses, since the glasses do not contact the cornea, their lens is located at a distance from the eye. You just need to wait a certain time to choose the right glasses.
Ordinary contact lenses ( daytime). Patients who, for one reason or another, could not adapt to the use of night lenses, or they have any contraindications, switch to day lenses. The fact is that hard night lenses are not as comfortable to wear as soft daytime lenses ( which after putting on are practically not felt). Before fitting day lenses, you need to wait until the cornea returns to its natural shape after the night correction is cancelled.
Laser vision correction. In principle, laser vision correction has the same goal as the correction with night lenses. During the operation, the cornea will be shaped with a laser to achieve 100% visual acuity. The difference is that this change is irreversible, and the shape does not need to be maintained by putting on lenses every night. Before the operation, it is very important not to use night lenses for a long time, so that you can accurately calculate the parameters of changes during the operation.

Thus, after night lenses it is easy to switch to another correction method, but this takes some time. The fact is that when the patient stops using the lenses, the shape that they gave to the cornea returns to its original parameters gradually. This time depends on how long the patient has been using night lenses ( the longer, the more stable the effect persists). It is believed that the cornea is guaranteed to return to its original shape in 6 months. That is, before the selection of glasses, contact lenses or laser correction, you must stop using night lenses six months before. In some cases, when the patient has worn these lenses for a short time and irregularly ( up to six months), the shape of the cornea can recover faster ( in a few months).

Premature selection of another method is fraught with the following problems. For example, the patient picked up glasses a month after he refused night lenses. During this period, the cornea has not yet acquired its original shape. The patient's vision seems to be better than it actually is, as there is a residual effect from prolonged use of night lenses. As a result, the doctor simply will not be able to objectively assess visual acuity when choosing glasses. When the patient's vision deteriorates further ( the residual effect of the night lens will pass), you will have to re-select new glasses.

The reverse transition from other correction methods to night lenses does not present any difficulties, since neither day lenses nor glasses give such a “residual effect”. You can objectively assess the visual acuity of a patient wearing glasses or contact lenses at any time. The exception is laser vision correction. After it, the use of night lenses may be contraindicated, since the thickness of the cornea has greatly decreased during the operation.

Is it possible to combine the use of night lenses with other methods of vision correction?

None of the vision correction methods is universal, and each of them has its own indications and contraindications. In this regard, there is a certain category of patients who have to combine several methods in order to achieve the required visual acuity. Correction with night lenses, as a rule, goes well with other methods and helps such patients.

Night lenses are convenient to combine with the following methods of vision correction:

Glasses. Glasses can help some patients who require complex correction. The fact is that several factors affect good vision at once. For example, if a patient has strabismus and myopia, only night lenses will not give a complete correction. They will correct myopia, and strabismus will need to be corrected with the help of prismatic lenses ( special glasses).
Soft daily lenses. Day lenses in combination with night lenses may be required for patients with severe astigmatism or a high rate of myopia ( more than -6 diopters). With night lenses it will be possible to compensate for 4 - 5 diopters, and to correct the remaining ( 1 - 2 diopters) daily lenses or glasses are required. Wearing soft day lenses will not affect the therapeutic effect of night lenses, as they will not put pressure on the cornea and will not spoil the “cast” that the orthokeratological lens left overnight.

In general, the possibility and expediency of a combination of several methods of vision correction should be discussed with the attending physician.

night lens care

Care of night lenses is extremely important for effective vision correction by this method. That is why, in the selection process, the doctor pays attention not only to the correct choice of lenses ( by diopter), but also provides detailed instructions to the patient. Improper care of the lenses will not only make them useless, but also increase the risk of various complications.
When caring for night lenses, pay attention to the following details:

container for storing lenses;
liquid for lens care;
storage of suction cups for lenses ( if the patient uses them);
proper lens cleaning.

Solution ( liquid) for storing night lenses

There are several types of liquid for storing night lenses. All of them are designed to moisturize the material from which the lens is made, extend its shelf life, kill pathogenic bacteria, and make it easier to remove and put on lenses.

For optimal correction with night lenses, you must adhere to the following rules:

use the solution recommended by the doctor when choosing lenses ( it is best suited for the selected lens type);
do not switch from one solution to another without consulting a doctor;
use the solution as indicated in the instructions ( in the right amount and for the intended purpose);
do not use an expired solution.

Containers for storage of night lenses

Containers are designed to store night lenses during the day. Before placing the lens in the container, it is filled with fresh solution. This ensures good safety of the lenses and significantly reduces the risk of pathogenic bacteria getting on their surface. The type of container and the manufacturer are not critical. It is only important to use the container as indicated in the instructions ( or as shown and explained by the physician instructing the patient). If the container is damaged, it must be replaced immediately. The average shelf life of a night lens container is 3 months.

How are night lenses, suction cups and containers cleaned?

Mechanical cleaning of night lenses is one of the regular procedures that must be performed correctly by the patient. The lens is cleaned with a special tool, applying a small amount of liquid to it and gently rubbing between the fingertips. This cleaning takes approximately one minute. Applying too much pressure with your fingers can damage the lens. The cleaning solution is evenly rubbed over the entire surface ( both external and internal). There are special brushes and other devices for cleaning lenses. It is better to consult with an ophthalmologist or orthokeratologist about the advisability of their use.

What is the expiration date of night lenses and how long can they be worn?

The vast majority of night lenses produced by manufacturers are designed for use within 1 year. This period is explained by the characteristics of the material from which the lens is made. Due to periodic donning and doffing, as well as contact with liquids ( tear moisture, cleaners in a container, etc.) the product may retain its shape worse, and the material itself may undergo a number of chemical changes. In principle, this does not mean that in a year and one day the night lens will no longer correct vision. Theoretically, it can perform its functions for quite a long time. But according to the generally accepted standard, in order to exclude the slightest possibility of harm to the body, it is better to replace it. This is usually specified in the contract that the patient enters into with the clinic that made the selection.

Early lens replacement earlier than a year) may be needed in the following cases:

the appearance of scratches on the surface of the lens;
clouding of the lens possible with improper care);
lens edge damage small chips, etc.);
lens loss;
the appearance of plaque or accumulation of substances that are not removed during the cleaning process;
incorrectly fitted lens often replaced free of charge in the same clinic under contract);
manufacturer's specific expiration date recommendations certain types of lenses may have special prescriptions and recommendations).

Regardless of the reason why a replacement is needed ( planned or early), it is best to contact the same clinic that selected the lenses. This will speed up the re-selection and fabrication process and save money. Usually the contract between the patient and the clinic provides for such situations.

Where and how to choose night lenses?

Due to the rapid development of orthokeratology, there are more and more specialists in this field. Today, their services can be used in almost any major eye clinic or vision correction center. Opticians and optometrists' offices are also beginning to appear, staffed by specialists who have undergone the necessary training. When contacting such clinics, the patient will be fitted with individual night lenses. It is recommended to see the same center or the same specialist in the future, as this will facilitate the procedure for changing lenses in the future. In many clinics, periodic consultations with a doctor after ordering night lenses are provided free of charge, and re-ordering, if necessary, replacement of night lenses is done at a discount.

Which doctor selects night lenses ( orthokeratologist, ophthalmologist, etc.)?

Unlike ordinary glasses and lenses, vision correction with night lenses requires special skills, so not every ophthalmologist can fit them. Doctors who deal with such correction are called orthokeratologists. They undergo a special training course and receive a separate certificate. Night lenses can also be fitted by a qualified optometrist. Differences in the selection technique come down to the use of special equipment and special calculations. Properly fitted orthokeratology lenses provide perfect reshaping of the cornea and provide near 100% vision throughout the day. A doctor who has not undergone special training will not be able to calculate the shape of the lens and give the correct parameters for its manufacture. Moreover, the wrong lens can reduce visual acuity and even damage the cornea. In addition, custom night lenses are significantly more expensive than regular contact lenses or spectacles, and the patient risks losing money for no benefit.

How is the selection of night lenses?

The selection of night lenses is a rather complicated procedure that requires the participation of both an orthokeratologist and the patient himself. For effective correction, it is necessary not only to make the lenses themselves correctly, but also to teach a person how to use them correctly. That is why the selection of any night lenses takes place in several stages. In addition, the clinic providing such services concludes a contract with the patient for a certain time, since after the selection, additional consultations may be needed. Most often, according to the contract, they are provided free of charge or at deep discounts.
It is believed that the selection of night lenses lasts about a month, during which the patient makes 4 scheduled visits to a specialist:

On the first visit, the doctor must determine whether the patient can, in principle, use night lenses as a method of vision correction. He conducts an examination to identify possible contraindications. If there are no contraindications, the doctor determines the parameters of the lens, which will give the optimal correction. Also on the first visit, the patient spends some time in trial lenses ( about half an hour lying with closed eyes). The specialist instructs on putting on, taking off and caring for night lenses.
Before the second visit, the patient spends his first night in his own lenses. In the morning, the doctor examines him, determines visual acuity and looks for side effects. After the first night, vision already improves significantly ( effect up to 75% of the planned correction).
A third visit is needed in about a week ( provided that the patient wore lenses at night all week). The doctor evaluates the effectiveness of the correction, which should already reach one hundred percent in the morning and only slightly decrease in the evening. He also looks for signs of side effects and possible complications.
The fourth scheduled visit will take place in about a month. The doctor re-examines the patient and evaluates his skills in lens care and use. An individual schedule is developed for further scheduled examinations ( on average, once a month).

In each case, the selection of night lenses may have some features. If there are complications from their use, short-term treatment or replacement of lenses may be required at any stage. In most clinics, all these appointments and treatments are included in the initial payment ( under the contract).

Are night lenses suitable for all patients?

Night lenses as a way to correct vision can help with most vision problems, but there are certain categories of patients who will have to resort to other methods.

Night lenses are usually not selected for the following groups of patients:

children under 6 years of age;
patients with severe farsightedness ( hypermetropia);
patients with presbyopia age-related farsightedness);
patients with various eye diseases and individual contraindications.

It should be noted that in recent years, night lenses that can correct farsightedness up to +3 - +4 diopters have gradually become widespread, but they are still difficult to find on the market. Patients with astigmatism also cannot always count on a complete correction ( one hundred percent vision) using night lenses. In order to check the possibility of orthokeratological correction in a particular case, you should contact an ophthalmologist or optometrist. Despite a fairly wide range of contraindications, many patients can still use this particular method. In addition, the technologies for manufacturing and fitting night lenses are improving every year, and the number of people who do not fit them is steadily decreasing.

What should I do if one of the night lenses is broken or lost?

The night lens is selected based on the individual characteristics of the cornea, and there are minimal differences in each eye. In this regard, the loss or breakage of one of the lenses does not require replacement of the entire pair. Moreover, at the stage of getting used to the lenses, some patients somehow have to change the lens if they cannot get used to it. The procedure for refabrication of an orthokeratology night lens is quite simple.

A clinic that offers such services usually contracts with each individual patient. This contract provides significant discounts for re-fitting or manufacturing of lenses, as well as preventive medical examinations. If the lens is lost, the patient should simply go to the same clinic where he picked up the lenses. Under the contract, it will be re-manufactured at a big discount ( and in some centers - even free of charge, depending on the terms of the contract).

Is it possible to order night lenses online or are they selected individually?

From a professional point of view, buying or ordering any optical correction means without a preliminary examination is a big risk. However, ordinary contact or spectacle lenses, in principle, can be bought without selection and "guessing". They can fit and provide a normal correction. In the case of night lenses, this is basically impossible.

Ordering online or buying ready-made orthokeratology lenses is not practiced for the following reasons:

each lens is made individually, based on the parameters of the cornea in a particular patient ( shape, diameter, curvature, etc.);
An “alien” lens with one hundred percent probability will not provide vision correction;
no major manufacturer of night lenses sells "replacement" lenses that can be bought without consulting a doctor;
The trial lens kits that an orthokeratologist has are intended to guide the selection of parameters during the procedure, and not to be purchased and worn by the patient.

Thus, the only solution is to contact a qualified specialist who will select and order an individual lens that is suitable for a particular person. Before use, you should consult with a specialist.

At first glance, why does a sleeping person need contact lenses - in order to see dreams better? In fact, this is the latest method of vision correction. In ophthalmology, it is called orthokeratology or OK therapy, which is used for myopia and astigmatism.

OK lenses (Ortho-K lenses) have a reverse geometry (the center is flatter than the periphery). The manufacture of such lenses became possible at the turn of the 80-90s of the last century with the advent of computer-controlled lathes.

Night lenses are an effective alternative to glasses and laser surgery. They are also indicated for unsuccessful eye surgeries (in this case, OK lenses are worn during the day). Night lenses are indicated for people 7-40 years old, whose myopia is up to 6 diopters and up to 1.5 diopters with astigmatism. But these are average indicators, often performance is achieved with higher diopters.

The effect of surgery

"Lenses for the night" are used only as directed by ophthalmologists. They are individual for each person. They are put on before going to bed and taken off in the morning. There is no need for lenses during the day, a person sees perfectly. That is, in order to see well during the day, you need to sleep in lenses at night.

Night lenses have two surfaces that differ in shape: the outer one is optical, like ordinary lenses, it is this that provides one hundred percent vision. The inner (active) one has a complex surface, with the help of which the tear film is affected and the relief of the cornea changes, it becomes flatter.

Compared to traditional contact lenses, which cover the cornea during the day and the eyes can only "breathe" at night, OK lenses have the opposite principle of operation: during the day the cornea "breathes" and at night it is covered by a gas-permeable lens.

Thanks to this, in simple terms, at night, under the pressure of the lens, the shape of the cornea changes, and in the morning it retains its accepted shape, providing clarity of vision during the day. However, this is only a temporary effect, you have to put on lenses again at night, because. the former form of the cornea returns in just a few days, and with it the former vision.

Every 3 months, you need to undergo a follow-up examination with your ophthalmologist.

Night lenses are durable, do not dry out, but require gentle care compared to soft contact lenses.

They are safe to wear and have no side effects if all the rules for caring for them are observed.

golden triad

The golden triad of night lenses is formed by Emerald of the American manufacturer Euclid Systems Corporation, Contex OK-Lens and ESA.

Emerald lenses have a blue tint, the material is oprifocon, the oxygen permeability of the lenses is 85 Dk/t.

Сontex OK-Lens are made of Nelfilcon using AQUA COMFORT technology, thanks to which dry eyes are eliminated, during each blink they are moisturized. In this case, the oxygen permeability is 100 Dk/t. In addition, the lenses are UV protected.

ESA also has an oxygen permeability of 100 Dk/t. But they are used not only for myopia (up to minus 6 diopters), but also for hyperopia (up to plus 3 diopters) and astigmatism (up to 3 diopters).

All these lenses are made by turning, they have in common durability, but the surface must be protected from scratches.

Night lenses are smaller in diameter than traditional counterparts, which ensures a good exchange of tears and nourishment of the cornea.

The lenses are designed to be used throughout the year.
For domestic ophthalmology, orthokeratology is still a novelty, but its use gives a quick positive effect. With its help, people with vision problems see well during the day, and the process of vision correction takes place at night, when a person is sleeping.

Nearsightedness, or scientifically myopia, is a common visual impairment observed in both adults and children. This disease is not characterized by pain or deterioration in general well-being, but it causes many problems in professional activities, studies and forces you to wear glasses or lenses. Different types of lenses are much more convenient than glasses, they do not change the appearance, do not fog up and allow you to do what you love. Night lenses for vision correction have replaced the usual means familiar to many.

Abroad, a similar technique (it is called orthokeratology) has been used to improve vision since 2002, in our country it is only gaining popularity, so many are skeptical about the new method of diopter correction.

The mechanism of action of night lenses

The first thing that distinguishes night lenses from day lenses is their structure - they are hard and it seems that it will hurt the eyes in them. But this is not entirely true, a slight discomfort is observed in the first few times of their use, then the eye fully adapts to them. They are put on with a small pipette 10-15 minutes before bedtime, to correct myopia, it will take about 8 hours of a good night's rest. Night lenses are cared for in the same way as day lenses, they are also processed and stored in a special solution.

The principle of operation of night lenses is based on the effect on the cornea. Rigid correction for several hours of sleep at night presses down the center of the outer surface of the eye, thereby changing the shape of the cornea. It becomes flat and the image is able to be fixed on the retina, as it should be in normal vision. The correct shape of the cornea lasts for a day or more, then it becomes convex again. That is why the effect of using hard lenses is fully preserved throughout the day, the next day a person sees worse. Each patient of the ophthalmologist chooses the mode of use of night lenses independently, but usually it is night after night or daily use.

At the first application, vision correction will be incomplete, clear vision will appear after 3-4 times of using the technique. In the first days, there may be a slight doubling of objects, lack of clarity, blinding from bright light sources. Usually these phenomena disappear within a week, otherwise an ophthalmologist's consultation is needed. The action of hard lenses is compared with laser exposure to the eye, the only difference is that the positive effect of their use will be temporary, not permanent.

Indications and contraindications of orthokeratology

Night hard lenses can be used to improve vision from the age of six. In some cases, this technique is the only option to prevent a fall in diopters in children, since they are prescribed a surgical operation only after 18 years. In any case, before using the technique, it is necessary to undergo a complete examination by a doctor, it is the ophthalmologist who selects them, focusing on the percentage of myopia, the condition of the entire eye. Rigid lenses are not prescribed for insufficient tearing, inflammation of the cornea. It will not be possible to fit the lens to patients with anatomical eye defects, such as corneal protrusion.

Basically, orthokeratology is indicated for the following categories of patients:

Children and adults under 40 with diopters from -1.5 to -6;
People who, due to the specifics of the profession, cannot wear contact lenses and glasses. This is usually observed when working with aggressive substances, dust. It is inconvenient to use lenses for firefighters and the military of some branches of the armed forces;
Patients for whom eye surgery is contraindicated due to heart disease.

When using lenses, some patients may experience slight swelling, redness of the sclera, and infectious diseases. This may be due to the wrong size of the lenses or non-compliance with the rules of asepsis during their storage. If these phenomena do not go away after the preventive measures recommended by the doctor, then improvement in vision will need to be achieved in other ways.

Advantages and disadvantages of orthokeratology

People using night lenses have already been able to appreciate their main advantages. And among the most important stand out:

No need to wear glasses and lenses during the daytime. For people of some professions, this is a fundamental point when choosing a night vision correction method;
The use of night lenses can stop vision loss in children;
The cornea does not suffer from a lack of oxygen during the day, while there is less likelihood of developing allergic reactions and conjunctivitis;
Orthokeratology allows you to practice sports such as swimming and cycling;
The absence of lenses during the daytime allows you to use any cosmetics;
Simplicity and ease of use;
The gas permeability of the lenses does not interfere with the supply of oxygen to the eye.

Despite the fact that lenses for vision correction are convenient and practical, they also have a number of some disadvantages that will not allow using this method of improving vision.

The main disadvantages of night lenses:

Price. Compared to ordinary day lenses, night lenses are much more expensive, from 10 thousand rubles and more. But this drawback is relative, since the lenses last for a whole year of use. Therefore, convenience is much more important for many than the price range, and once a year you can spend a similar amount on your health.
The fragility of the material from which the lenses are made. When dropped, they may break;
The possibility of swelling and inflammation, but contact lens lovers are not immune from this.

Night lenses are only becoming popular and widespread, many find only disadvantages in their use, other significant advantages. This is exactly what happened several decades ago with the advent of the first contact lenses, on Today, lenses have replaced glasses for many. Many doctors believe that night lenses are the future and their further improvement will allow correcting the vision of people with myopia greater than 6 diopters.

Night wear lenses — modern know-how in ophthalmology. This method is designed to combat the most common visual impairment -. The therapeutic effect of lenses occurs during a night's sleep, in the morning 100% vision returns to the patient. Such a result seems almost fabulous, however, it is based on scientific knowledge and many years of research experience.

A bit of history

Orthokeratology, as a vision correction technique, began to develop in the 60s of our century. The first lenses were used for a long period, full restoration of vision was not always achieved, positive results were unstable.

The development was saved by the appearance in the early 90s of new technologies in the manufacture of lenses. They had a more complex and perfect geometric structure. New milestone in development orthokeratology led to the practical application of this method for the treatment of visual pathologies since 2000.

The essence of the method

In healthy people, the image is focused on the retina, and in patients with myopia in front of it, because the affected lens cannot refract light rays correctly. Night wear lenses OK-lenses) "compress", making it flatter, which helps to project images directly onto the retina.

This form is preserved during the daytime, it is during this period that patients see perfectly and the need to wear glasses and contact lenses is completely eliminated.
However, this effect is reversible, the shape of the cornea returns to its original state and requires the use of orthokeratological lenses again.

Video:

For which diopters are night lenses indicated

Complete vision correction is achieved in people with- 1.5 to - 5.0 diopters.
There is evidence of positive results in patients with deviations of -6 diopters.

The positive effect is achieved gradually. In the first days of using lenses, vision is restored to 70-75%, after 1-2 weeks of use - up to 100%.

The worn mode is selected individually either every night or every other night, depending on the result.

Night lenses in the elderly

Night lenses for vision correction have no age restrictions, they are used to restore vision in children and people of mature and old age.

Price

The price for this type of therapy remains quite high, on average it is less. This is due to the novelty of medical technology, a small number of specialists in this field, long-term selection of lenses and constant medical supervision over their use.

If we talk about specific numbers, then the cost of one pair of lenses for night wear can be from 13 to 20 thousand rubles in 2017 . Usually, this price includes an examination and consultations with a doctor from whom you will purchase your lenses and be observed for your problem.

However, these lenses can be used for a very long time and do not need to be replaced frequently. The convenience of their use justifies the cost of this type of therapy, because the whole day patients feel healthy and can do what they love, without wearing glasses or vision correction. In addition, OK lenses are a therapeutic alternative for people who are contraindicated in surgery, wearing or daytime contact vision correction.

Night lenses for children

Huge advantage of the use of lenses for children is that when they are used, they can maintain their usual motor activity. The risk of injury to the mucous membrane of the eyes, as with the constant wearing of contact lenses, is much less.

In cases of progressive myopia, the orthokeratology technique is indispensable, since surgical correction of vision cannot be performed until the age of majority of patients. In addition, the process of wearing OK lenses is under constant parental control unlike other traditional means.

Motivating children to wear glasses is very difficult, they can take them off in the company of their peers to look like everyone else, they can forget them at home, break them and get injured. Wearing is impossible in children in the younger age category, it is fraught with improper care by the penetration of microbes into the mucous membrane of the eye and development. These situations can be avoided by orthokeratological method.

Night vision correction method for adults

The use of OK lenses is especially important for people with certain professions.
Builders, miners, drivers, nightclub workers are constantly faced with smoke and dust in the environment. In such conditions, wearing glasses and contact lenses is a real test, they are constantly dirty, lose their sharpness.

In a sports environment with increased physical activity and risk, wearing traditional vision correction means is very difficult, and in some cases even dangerous.
Therefore, night vision lenses are recommended for many people to ensure comfort and safety in the workplace.

The use of night contact lenses to restore vision is an effective and harmless way to treat myopia and myopic astigmatism. In many cases, regular wearing of rigid night lenses allows you to restore and improve vision without resorting to surgery. However, unfortunately, this method of vision correction has a number of contraindications, in the presence of which the use of night lenses is ineffective.

Contraindications for the use of night lenses in ophthalmic diseases

One of the main obstacles to the use of night lenses is the presence of a number of ophthalmic diseases. First of all, contraindications for the treatment of ophthalmic disorders with the help of night lenses are the presence of chronic or acute inflammatory eye diseases of various origins, including conjunctivitis, keratins, uveitis and other disorders, as well as severe dry eyes. The use of lenses, in this case, significantly increases the risk of further infection, complications and damage to the eye membrane. The use of lenses becomes possible only after the elimination of the infection and complete recovery.

In addition to infectious diseases, other equally important contraindications for the use of night lenses are the presence of congenital or acquired eye pathologies or anomalies. Wearing night lenses, in this case, is capable of provoking the further development of pathology. For example, in the presence of corneal diseases such as keratoglobus and keratoconus, lenses can lead to further thinning of the central corneal zone. Among the contraindications prohibiting the use of this technique are also: various diseases of the eyelids, rigidity of the upper eyelid, lagophthalmos; the presence of complex eye diseases, in particular cataracts and glaucoma; the presence of moderate astigmatism (1.75 and above diopters); low sensitivity of the cornea of the eye.

The negative consequences of using night lenses in the presence of contraindications can manifest themselves in disorders and deterioration of vision associated with a change in curvature in the central zone of the cornea, mechanical eye injuries or other serious complications.

Contraindications for the use of night lenses in general diseases

In addition to ophthalmic diseases and pathologies, the use of night lenses is also contraindicated in the presence of certain common diseases and conditions. In particular, the use of the treatment is contraindicated for allergies. Allergic reactions in the form of itching, pain in the eyes or increased tearing, may cause the lens material or means of treatment. If within a few days the symptoms do not disappear, it is necessary to abandon the use of lenses, in order to avoid complications. Temporary restrictions for the use of this method of treatment are also the presence of colds and infectious diseases of a general nature, accompanied by fever and general weakness. The presence of an infection in the body increases the risk of developing complications resulting from a decrease in immunity. There are also some restrictions for treatment with night lenses for people with endocrine disorders. In each case, the decision on treatment is made individually, depending on the severity of the disease.

Other contraindications

Relative contraindications or rather temporary restrictions for the correction with the help of night lenses are pregnancy and lactation, as well as children under 6 years of age. Some ophthalmologists also advise against the use of night lenses for older people, in particular, because of the high risk of mechanical damage to the eyes. In order to avoid mechanical injuries, it is also not recommended to use night lenses in a state of alcoholic or drug intoxication.

Despite the presence of contraindications, night lenses, subject to the recommendations of an ophthalmologist and the basic rules for their use, can significantly improve and restore vision.